Steel Industry

a metal mine is one of the commodity industries. In normal mode these are indestructible.

It will produce iron, bauxite and copper on a monthly basis and depending on on the stone quarry next to it.

The metal mine will also upgrade itself on a higher level when their balance is enough to pay the upgrade. The base upgrade time is about 8 weeks and the industry will produce the normal amount while upgrading and when finished it will upgrade the production rate.